1. Field of the Invention
The present invention relates to a branch connection, and in particular a drain branch connection in a main flexible pipe, reinforced or not, sheathed or not.
2. Description of the Prior Art
The French patent application No. 81 10769 describes a branch connection whose distal end is preferably separated from the wall of the main pipe or at most in contact therewith, so as to protect the armature of the connection and/or of the main pipe by penetration of a coating of a junction material, shaped by molding, between the branch orifice formed in the main pipe and the connection.
This connection is formed particularly when it is a question of a drain connection, by a tubular insert embedded at least partially in said coating of junction material.
Before molding this coating, a binding material is applied (by spraying or by immersion or similar) to at least the parts of the insert intended to be coated with said junction material, more particularly for promoting adherence of the coating to the insert during molding (it is a question of hot molding).
The insert cooperates with a part intended to seal the proximal end of this insert, which part is provided with means for effecting draining without completely removing the sealing part: for this, the part in question is formed by a threaded tubular plug intended to be screwed inside the previously tapped insert and its lateral wall is provided with a drain orifice formed in the upper part.
The purpose of the present invention is to provide a branch connection, and more particularly a drain branch connection which answers better the requirements of practice than the connections relating to the same purpose known heretofore, particularly:
in that the drain connection of the invention has: PA1 in that there is no need to apply bonding material to this connection (insert) before molding, which simplifies the fitting of a drain connection. PA1 its distal end preferably separated from or at most in contact with the wall of said main pipe; PA1 the shape of a tubular insert embedded at least partially in said junction material and cooperating with a part intended to seal off the priximal end of this insert, and PA1 means for effecting draining without completely removing said part,
a better fatigue resistance (and so better sealing behavior), PA2 a fatigue resistance which is more constant in time (less aging), and